Formation behavior of CaCu_3Ti_4O_(12) from CaTiO_3, CuO and TiO_2

摘要

The formation behavior of CaCu_3Ti_4O_(12) (CCTO) had been investigated via solid state reaction from CaTiO_3, CuO and TiO_2 powders. In the temperature range from 750 to 1,200 ℃, the reaction sequence was traced by XRD, and the microstructure evolution of calcined powders was also investigated by SEM. CCTO began to form owing to the reaction between CaTiO_3, CuO and TiO_2 at around 850 ℃, and became the major phase at 1,000 ℃. Finally, the single phase CCTO was obtained at 1,150 ℃. However, CCTO was decomposed at CaTiO_3, CuO and TiO_2 when the temperature increased to 1,200 ℃. In addition, no other intermediate phases occurred in the synthesized process. The formation behaviors indicated that CaTiO_3 prevented the formation and growth of CCTO.